Heated roller and method of heating the same

ABSTRACT

A hollow roll is mounted on a shaft by journal means. The shaft has an axial passage through which a heated lubricant fluid is supplied, part of which is circulated to the journal means to lubricate the same and the remainder of which is circulatedbypassing the journal means-directly into the interior of the roll for heating the latter.

o I 11111112 States Patent 11 1 [111 3,794,1 1 Bauch 1 Feb. 26, 1974[54] HEATED ROLLER AND METHOD OF 3,302,698 2/1967 Edwards 165/89 HEATINGT SAME 3,477,499 11/1969 Ctoetz 1 165/86 3,583,687 6/1971 Nukahara165/90 [75] Inventor: Ernst Bauch, Bordesholm, Germany [73 Assignee:Neumunstersche Maschinen-Und Apparatebau Ge ell hafg b,][{,, PrimaryExaminer-Charles J. Myhre Neumunster, Germany Assistant ExaminerTheophilW. Streule, Jr. Attorney, Agent, or Firm-Michael S. Striker [22] Filed:Nov. 16, 1971 v i [21] Appl. No.: 199,124

[30] Foreign Application Priority Data [57] ABSTRACT Nov. 21, 1970Germany 2057391 Dec. 8, 1970 Germany 7045194 A hollow roll is mounted aShaft y journal means- The shaft has an axial passage through which aheated [52] 11.5. C1. 165/90, 34/124 lubricant fluid is Supplied, p ofwhich is u a d 151 1 1m. 01. F2811 11/02 to the jo means to lubricate hm n the re- 1511 Field 01 Search 165/8690; 34/124 mainder of which iscirculated-bypassing the journal means-directly into the interior of theroll for heating [56] References Cited the iattef- UNITED STATES PATENTS2,933,760 4/1960 10 Claims, 2 Drawing Figures Heide 165/89 X x4 I F [it]1 1 1 L E E1 Jfi PATENTEU FEBZS I974 SHEET 1 [1F 2 INVEOR ATTORN EYPATENTED FEBZB I974 sum 2 OF 2 INVENOR ATTORNEY HEATED ROLLER AND METHODOF HEATING THE SAME BACKGROUND OF THE INVENTION The present inventionrelates generally to heated rolls, and more particularly to rolls of thetype which are used to heat and, sometimes, to advance textilefilaments, ribbons composed of such filaments, textiles in general andthe like. The invention also relates to a method of heating andlubricating such a roll.

It is already known that textiles made of filaments, particularlysynthetic plastic material, ribbons or tapes made of such filaments, orthe filaments or yarns themselves, must quite often be heatedpreparatory to further processing. A variety of different approaches isknown for effecting such heating, and this includes the use of rollswhich are heated to the requisite temperature by passing a heating fluidthrough them, with the filaments or textiles passing over the rolls andbeing heated by contact therewith.

The rolls of this type which are known from the prior art are usuallymounted on a shaft which is journalled on a housing and either rotateswith the roll or is itself driven and fixed with the roll. Specialguidance devices having a sealing function are utilized to supply theheating fluid to the rotating shaft, where it passes through a bore inthe center of the shaft to a distributing point in order to pass fromthere into the hollow jacket or circumferential wall of the roll. Afterpassing through this hollow wall, the heating fluid is returned back tothe rotating shaft and is centrally evacuated from the shaft in axialdirection of the latter, usually through a second passage whichgenerally concentrically surrounds the first passage through which thefluid is originally supplied. Experience has shown that these priorartconstructions have certain significant disadvantages. Among these is thefact that to obtain the necessary circulation of the heating fluid atleast two rotary seals must be provided, namely where the heating fluidis admitted into the rotary shaft and where it is evacuated from thelatter. Furthermore, the necessity to have the incoming and outgoing(that is the fresh and the spent) heating fluid pass through one and thesame shaft, a temperature equalization between incoming and outgoingheating fluid takes place so that it is necessary for the incomingheating fluid to be heated to a significantly higher temperature than isactually necessary to heat the roll to the requisite degree. In otherwords, this higher temperature is necessary in order to compensate forthe heat losses resulting from heat exchange of the incoming heatingfluid with the cooler outgoing heating fluid. It goes without sayingthat a corollary of this is the fact that it is difficult 'to maintainthe temperature constant. In addition, many of the prior-artconstructions require a second circulatory arrangement through whichlubricating fluid for the journals of the roll and often also for thedrive of the roll is supplied, again requiring additional seals.

SUMMARY OF THE INVENTION It is a general object of the invention toprovide an improved roll of the type here under discussion which avoidsthe disadvantages of the prior art.

An additional object of the invention is to provide such an improvedroll in which the structural measures required for effecting thenecessary circulation of heating and lubricating fluid are very simple.

A concomitant object of the invention is to provide such a roll whichcan be readily assembled and disassembled with the remaining associatedcomponents without having to fear the possibility of damage or the like.

A concomitant object of the invention is to provide a method of heatingand lubricating such a roll.

In pursuance of these objects, and of others which will become apparenthereafter, one feature of the invention resides in an arrangement of thecharacter here under discussion, which comprises a shaft and a hollowroll surrounding at least a portion of this shaft. Journal meansjournals the roll for rotation and supply means supplies a flow ofheated lubricant fluid. First guide means guides some of this heatedlubricant fluid to the journal means for effecting lubrication of thesame, and second guide means guides the remainder of the heatedlubricant fluid directly into the interior of the hollow roll, bypassingthe journal means, for effecting heating of the roll.

It will be immediately evident that a significant advantage of theconstruction according to the present invention is the fact that one andthe same fluid is used both for heating purposes and for lubricatingpurposes, and this may be an oil which at the requisite temperatures iscapable of affording the necessary lubricating action. Such an oil maybe on mineral oil basis or it may be a synthetic flowable lubricant.Inasmuch as only a single fluid circulatory system is required with theconstruction according to the present invention, the number of sealswhich always are subject to deterioration and malfunctionis reduced toan absolute minimum.

Furthermore, by guiding only a smaller portion of the incoming heatedlubricant fluid to the journals for lubricating purposes, and having thelarger remainder of the heated lubricating fluid bypass the journalmeans and enter directly into the roll for heating it, the pres sure atwhich the fluid must be supplied in order to assure its propercirculation through the roll can be substantially lower than wouldotherwise be possible. Among the obvious advantages of this feature isthe fact that there is less danger of leakage at those seals which muststill be provided despite the significantly simplified construction.

The type of arrangement here in question is usually provided with astationary housing in which the drive means for the roll is located. Inorder to eliminate the complicated return of the spent heating fluidthrough the shaft, and also to eliminate the heat losses resulting fromsuch an expedient, the invention also proposes that the spent heatingfluid be directed into the stationary housing from where it can berecirculated to the supply means. This results in a further reduction inthe number of sealing arrangements which must be provided in theconstruction according to the present invention as opposed to thoseknown in the prior art, and permits a still further simplifiedconstruction.

In the prior-art construction it has been found particularlydisadvantageous that the seal at the inlet of the heating fluid into therotary shaft was subject to frequent malfunction, not the least becausethe heating fluid at this point must be under high pressure in order toassure a rapid flowing through the various passages. As a result, suchseals are subject to high stresses and invariably had to be ofcomplicated and expensive construction in order to provide even areasonably reliable sealing effect. This difficulty is overcome by thepresent invention which proposes to utilize a stationary shaft with thehollow roll rotating with reference to the stationary shaft. With thisconstruction according to the present invention the most heavilystresses rotary seal required in the prior-art constructions is avoided,because the heated lubricating fluid can now be supplied through thestationary shaft into the roller, for instance through a' bore providedin the center of the shaft. This means that it is sufficient to providea single rotary seal, namely between the stationary housing and theroll, and this seal is not subject to any particular stresses because itis located in the outlet region where the heating and lubricant fluidissues from the shaft and is under less pressure than in the inletregion. Even if the roll is positively driven, it is merely necessary toprovide an additional seal at the entry point of the drive shaft, andthis seal also is not subject to any particular pressures.

The fluid flow through the hollow roll can be further improved inaccordance with the present invention by surrounding the shaft withinthe roll with a tubular member which defines with the innercircumferential surface of the roll an axially extending annularclearance through which the lubricant fluid passes. This clearance maybe either smooth or may be provided with guide ribs for guiding thefluid passing therethrough.

If the roll is positively driven, then it is connected with a drivegear. While it is possible to make the drive gear fixed with the roll,it is preferred to connect the drive gear releasably with the roll inorder to facilitate disassembly of the arrangement and the removal ofthe roll from the shaft. In particular, experience has shown that thereis much more frequently a need for repair to be effected on the rollthan on the drive itself, and by releasably connecting the drive gearwith the roll the latter can be removed by itself whereas the drive gearcan remain in position.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary longitudinalsection, with parts illustrated diagrammatically, of one embodiment ofthe invention; and

FIG. 2 is a view similar to FIG. 1 but illustrating a further embodimentof the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing now the drawing indetail, it will be seen that in FIG. 1 I have illustrated an embodimentin which the roll to be heated is identified with reference numeral 1and is mounted by means of journals 2 and 3 (here antifriction bearings)on a stationary shaft 4. The latter is provided with an axial passage orbore 5 provided with an inlet 6 with which it can be connected with asupply of heated lubricant fluid, so that such fluid is supplied viainlet 6 into the passage 5. The latter extends over the entire length ofthe illustrated shaft and communicates at the end portion of the roll 1which is closed with the transverse end cap 7 (that is the right-handend portion in FIG. 1) with the interior of the roll.

At this end portion the first guide means in form of one or morepassages 8 is provided which guides some (a smaller part) of theincoming heated lubricating fluid into and through the journal 3 whichis thus lubricated. The remainder (the larger part) of the incomingheated lubricating fluid is guided by second guide means in form of oneor more grooves 9 directly into an axially extending annular gap 10which exists between the inner circumferential surface of the roll 1 anda tubular member 11 which surrounds the shaft 4 within the roll 1 withradial clearance from the circumferential wall of the latter.

The lubricant and heating'fluid passes through the gap 10 and a smallerquantity of it passes through the journal 2, lubricating the same,before it enters into the passage 13 and from there into the stationaryhousing 14 which is diagrammatically illustrated. The major portion ofthe lubricant and heating fluid from the gap 10 passes through the guidepassage 12 and also into the housing 14 but bypassing the journal 2.

If the roll 1 is not positively driven (contrary to the embodiment ofFIG. 1) then the only rotary seal required for the arrangement is theseal 15 between roll 1 and stationary housing 14. If, however, the roll1 is positively driven, for instance by the illustrated gear 16 which isshown in FIG. 1, then an additional seal is required for the shaft ofthe non-illustrated second gear in the stationary housing 14, whichsecond gear cams with the gear 16 to transmit motion to the same andthereby to the roll 1.

The gear 16 can be fixedly connected with the roll 1 so that the twocannot be separated. However, it is advantageous as shown in FIG. 1 toconnect the gear 16 with the roll 1 by means of screws or bolts 16a sothat they can be separated fromone another. These screws or bolts 16acan be released after the annular carrier 17 carrying the seal 15 andmounted by means of screws or bolts 17a to the housing 14, is removed.After the end cap 7 is removed and the mount 19 for the journal 3, theroll 1 can be readily withdrawn and repaired, inspected or exchanged,whereas the gear 16 remains in position. Subsequently, thejust-described steps are reversed in order to connect the roll 1 againwith the gear 16.

If it should be necessary to remove the gear 16 itself, then the mount18 for the journal 2 must be removedin some circumstances also thetubular member 11whereupon the gear 16 can also be withdrawn axially ofthe shaft 4 for repair, inspection or replacement.

The seal 15 is entirely sufficient for sealing the stationary housing 14with respect to the rotating roll 1.

The heating and lubricating fluid which accumulates in the stationaryhousing 14 is withdrawn therefrom by means of the diagrammaticallyillustrated pump P and supplied via a conduit 6a to a suitable heater Hwhere it is reheated to the necessary temperature and then supplied tothe inlet 6. It is also possible to provide a device for subjecting thefluid to cleaning or filtration if and when this should be necessary.Such devices are well known, as are the heaters H.

The highest requirements in this arrangement are made of that portion ofthe fluid which serves to lubricate the gear 16, unless specialexpensive broad gears are to be used. in which the pressures which occurare lower than in conventional gears. To overcome the attendant problemsthe invention proposes that some of I the fluid withdrawn by the pump Pbe branched off from the conduit 6a at a distributing valve V, to besupplied by a branch conduit 6b first to a cooling device C (known perse to those skilled in the art) and then to the diagrammaticallyillustrated inlet port in the stationary housing 14 so that followingthe curved arrow it can be suppiied ta the gear 116. This means that thegear i6 is lubricated not only by the ambient fluid which is still inheated condition, but also receives lubrication from the additionallysupplied cooled fluid whose admixture with the heated fluid surroundingthe gear 16 reduces the temperature at this highest-stressed locationand increases the lubricating effectiveness of the fluid. Because thegear 16 and the second nonillustrated gear camming therewith are bothlocated in the stationary housing 141, no rotating seal is required forits supply either.

The embodiment in FIG. 2 is largely the same as that in FIG. 21, andlike reference numerals identify like components. Here, however, two ofthe rollers 1 are mounted on axially adjacent portions of the shaft 4which is again stationary, and all of the components associated in FIG.1 with the single roll 1 are also associated in duplicate form with thesecond roll 1 illustrated in FIG. 2. In this embodiment the passage 5extends throughout the entire axial length of the shaft 4 and a radialinlet port in the shaft 4 communicates with the passage 5 to supplylubricant and heating fluid thereto.

However, it should be noted that it is also possible (although notillustrated) for the shaft 4 to be provided with two separate bores 5which do not communicate with one another, that is each end portion ofthe shaft is provided with its own bore 5. In this case each of thebores 5 may have a radial inlet port so that heating and lubricatingfluid can be supplied to each channel 5 individually, establishing inthis manner two separate fluid circuits so that the two rolls 1 can beheated to different temperatures if desired.

It will be appreciated that the present invention provides for anarrangement and a method of operating this arrangement in which thedifficulties of the prior art are overcome and the objects of thepresent invention achieved.

It will be understood that each of the elements described above, or two'or more together, may also find a useful application in other types ofapplications differing from the types described above.

While the invention has been illustrated and described as embodied in anarrangement having a roll heated and lubricated with a single fluid, itis not intended to be limited to the details shown, since variousmodifications and structural changes may be made without departing inany way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can by applying current knowledgereadily adapt it for various applications without omitting featuresthat, from the standpoint of prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this inventionand, therefore, such adaptations should and are intended to becomprehended within the meaning and range of equivalence of thefollowing claims.

What is claimed as new and desired to be secured by Letters Patent isset forth in the appended 11. An arrangement of the character described,comprising a shaft; a hollow roll surrounding at least a portion of saidshaft; journal means journalling said roll for rotation; supply meansfor supplying a flow of heated lubricant fluid; first directing meansfor directing a major part of said heated lubricant fluid directly intothe interior of said hollow roll for effecting heating of the same; andsecond directing means for directing a minor part of said heatedlubricant fluid to flow initially through said journal means so as toeffect lubrication of the same, and to thereupon become united with saidmajor part downstream of said journal means so as to participate inheating of said roll.

2. An arrangement as defined in claim 1, wherein said shaft isstationary and said journal means journals said roll for rotation aboutsaid shaft.

3. An arrangement as defined in claim 2, wherein said supply meanscomprises at least one channel provided in said shaft and having aninlet end adapted to communicate with a source of said heated lubricantfluid, and an outlet end communicating with said guide means.

4. An arrangement as defined in claim 1; further comprising a tubularmember surrounding said shaft within said roll and defining with aninterior surface of the latter an axially extending annular clearancewhich communicates with at least said first directing means.

5. An arrangement as defined in claim 1, said shaft having two axiallyspaced portions and said roll surrounding one of said portions; andfurther comprising an additional roll similar to the first-mentionedroll surrounding the other of said portions, additional journal meansjournalling said additional roll, and additional first and seconddirecting means similar to the firstmentioned directing means butoperatively associated with said additional roll and said additionaljournal means.

6. An arrangement as defined in claim 1; and further comprising drivegear means journalled for rotation about said shaft, and connected withsaid roll for driving the same in rotation.

7. An arrangement as defined in claim 6; further comprising releasableconnecting means for releasably connecting said drive gear means withsaid roll in releasable relationship.

8. An arrangement as defined in claim 6; and further comprising conduitmeans for returning lubricant fluid from said roll to said supply means.

9. An arrangement as defined in claim 8; further comprising branchconduit means communicating with said conduit means and the region ofsaid drive gear means for branching off some of the lubricant fluid fromthe former and supplying it to the latter, and cooling means interposedin said branch conduit means for cooling the branched-off lubricantfluid upstream of said drive gear means.

lllll. A method of heating and lubricating a hollow roll journalled on ashaft via journal means, comprising the steps of supplying to saidhollow roll via said shaft a heated lubricating fluid; directing a firstpart of said Iuheating said roll; and reuniting said first part withsaid bricant fluid to flow through through said journal means forlubricating the same; directing the remaining second part of saidlubricating fluid directly into the interior of said roll, bypassingsaid journal means, for

second part downstream of said journal means so as to participate inheating of said roll.

1. An arrangement of the character described, comprising a shaft; ahollow roll surrounding at least a portion of said shaft; journal meansjournalling said roll for rotation; supply means for supplying a flow ofheated lubricant fluid; first directing means for directing a major partof said heated lubricant fluid directly into the interior of said hollowroll for effecting heating of the same; and second directing means fordirecting a minor part of said heated lubricant fluid to flow initiallythrough said journal means so as to effect lubrication of the same, andto thereupon become united with said major part downstream of saidjournal means so as to participate in heating of said roll.
 2. Anarrangement as defined in claim 1, wherein said shaft is stationary andsaid journal means journals said roll for rotation about said shaft. 3.An arrangement as defined in claim 2, wherein said supply meanscomprises at least one channel provided in said shaft and having aninlet end adapted to communicate with a source of said heated lubricantfluid, and an outlet end communicating with said guide means.
 4. Anarrangement as defined in claim 1; further comprising a tubular membersurrounding said shaft within said roll and defining with an interiorsurface of the latter an axially extending annular clearance whichcommunicates with at least said first directing means.
 5. An arrangementas defined in claim 1, said shaft having two axially spaced portions andsaid roll surrounding one of said portions; and further comprising anadditional roll similar to the first-mentioned roll surrounding theother of said portions, additional journal means journalling saidadditional roll, and additional first and second directing means similarto the first-mentioned directing means but oPeratively associated withsaid additional roll and said additional journal means.
 6. Anarrangement as defined in claim 1; and further comprising drive gearmeans journalled for rotation about said shaft, and connected with saidroll for driving the same in rotation.
 7. An arrangement as defined inclaim 6; further comprising releasable connecting means for releasablyconnecting said drive gear means with said roll in releasablerelationship.
 8. An arrangement as defined in claim 6; and furthercomprising conduit means for returning lubricant fluid from said roll tosaid supply means.
 9. An arrangement as defined in claim 8; furthercomprising branch conduit means communicating with said conduit meansand the region of said drive gear means for branching off some of thelubricant fluid from the former and supplying it to the latter, andcooling means interposed in said branch conduit means for cooling thebranched-off lubricant fluid upstream of said drive gear means.
 10. Amethod of heating and lubricating a hollow roll journalled on a shaftvia journal means, comprising the steps of supplying to said hollow rollvia said shaft a heated lubricating fluid; directing a first part ofsaid lubricant fluid to flow through through said journal means forlubricating the same; directing the remaining second part of saidlubricating fluid directly into the interior of said roll, bypassingsaid journal means, for heating said roll; and reuniting said first partwith said second part downstream of said journal means so as toparticipate in heating of said roll.